Neuroinflammatory effects of tDCS in ovariectomized rats with chronic inflammation

Introduction: Postmenopausal women are more susceptible to chronic conditions, such as osteoporosis, arthritis, and other inflammatory diseases. We investigated the effects of transcranial direct current stimulation (tDCS) on biomarker levels in ovariectomized rats subjected to an inflammatory model. Methods: Twenty adult female Wistar rats underwent ovariectomy and complete Freund's adjuvant (CFA)-induced inflammation. We divided them into 2 groups: OAS (sham tDCS) and OAT (active tDCS). Fifteen days later, the rats underwent bimodal tDCS treatment (20 min, 0.5 mA, 8 days). After 24 h of the last tDCS session, we killed the rats and collected tissue samples (hypothalamus, cerebral cortex, and brainstem) for biomarker analysis by ELISA. We removed the paws for histological analysis. Results: Active tDCS increased hypothalamic and cortical TNF-α and NGF levels, hypothalamic and brainstem IL-1ß levels, and hypothalamic IL-10 levels. Histology of paws showed an inflammatory profile. We observed a small tDCS effect, not statistically significant. Discussion: Bimodal tDCS had an effect on the central inflammatory axis, with a small effect on the peripheral site as evaluated by histology in the current study. (AU)

Cafeteria diet increases liquid intake and serum creatinine levels in rats

Introduction: Important changes in human dietary pattern occurred in recent decades. Increased intake of processed foods leads to obesity, which is related with the development of chronic diseases such as type 2 diabetes mellitus, hypertension, as well as cardiovascular and chronic kidney diseases. The prevalence of hypertension has also dramatically increased in recent years, and high sodium intake contributes to this scenario. In healthy individuals, kidneys are the primary end-organs that regulate sodium homeostasis. This study aims to evaluate renal function parameters and systolic blood pressure measurements in an animal model of obesity. Methods: Sixty-day-old male Wistar rats (n=30) were divided into two groups: standard (SD) and cafeteria diet (CD). Cafeteria diet was altered daily and was composed by crackers, wafers, sausages, chips, condensed milk, and soda. All animals had free access to water and chow and the experiment was carried out for 6 weeks. Weight gain, sodium and liquid intake control, systolic blood pressure measurements, and renal function parameters were evaluated. Results: Animals exposed to cafeteria diet had an increase of 18% in weight compared to the control group. Sodium intake was increased by cafeteria diet and time (F(1,28)=773.666, P=0.001 and F(5,28)=2.859, P=0.02, respectively) and by the interaction of both factors (F(6,28)=2.859, P=0.02). On liquid intake occurred only effect of cafeteria diet and time (F(1,28)=147.04, P=0.001 and F(5,28)=3.996, P=0.003, respectively). Cafeteria diet exposure also induced an increase on creatinine serum levels (P=0.002), however this effect was not observed on creatinine urine levels (P>0.05) nor on systolic pressure measurements (Students' t test, P>0.05). Conclusions: Obesity induced by cafeteria diet exposure increases liquid intake and alters creatinine serum levels, an important renal function marker. Considering the high consumption of hypercaloric food currently in the world, further studies are required to elucidate the modifications on renal function triggered by this diet over time (AU)

Evaluation of different procedure involved in the Transcranial Direct Current Stimulation (tDCS) technique experimental application

Introduction: The transcranial direct current stimulation (tDCS) is a non-invasive technique, which induces neuroplastic changes in the central nervous system of animals and humans. Furthermore, tDCS has been suggested as a therapeutic tool for pain management. The aim of this study was to standardize a non-invasive tDCS technique indexed by the nociceptive response of rats submitted to different conditions necessary to the tDCS application. Method: 60-day-old male Wistar rats (n=65), divided into 6 groups: control(C); non-active sham (NAS); active-sham (AS); active-sham restrained (ASR); non-active sham restrained (NASR); active tDCS treatment. Animals received treatment during 30 seconds (sham-active) or 20 minutes (restraint and tDCS)/8 days. Nociceptive threshold was assessed by Hot Plate test at baseline, immediately and 24h after the first session, immediately and 24h after the last session. Variance analysis of repeated measurements followed by Bonferroni was performed for intra-group comparison. Results: Physical restraint and 30 seconds stimulation (sham-tDCS) increased pain sensitivity (P≤0.05), and tDCS treatment was able to prevent the thermal hyperalgesia. Our original tDCS montage is similar to that used in the procedure with humans, because it is not an invasive technique. The electrodes are positioned on the head, and the animals are immobilized during the 20-minute treatment. As this procedure could involve behavior and neurochemical alterations due to stress induced by restriction (thus, it creates a research bias), we hypothesized that a 30-second electrical stimulus application (sham-tDCS) and the physical restriction used during tDCS treatment might alter nociceptive response in rats. Conclusion: There are methodological limitations in the present tDCS-technique. Although active-tDCS treatment is able to prevent these harmful effects, interference of these factors has to be considered during the results' analysis. Future adaptations of the tDCS-technique in rats are required to evaluate its therapeutic effects (AU)

Factors associated to salivary flow alterations in dry mouth female patients / Fatores associados a alterações no fluxo salivar em pacientes com xerostomia

BACKGROUND AND OBJECTIVES: Saliva plays an important role in oral health; it is involved in lubrication of the oral mucosa, protection against infections, transport of nutrients and digestive enzymes, remineralization of teeth, as well as aiding in chewing, swallowing and speech. Reductions in the amount of saliva are known to increase the risk of oral diseases. This study investigated the factors associated to salivary flow alterations and its relationship with age, burning mouth syndrome, psychiatric and sleep disorders, systemic diseases and chronic drug use. METHODS: A total of 30 patients complaining of dry mouth without unbalanced systemic diseases were included. Questionnaires regarding socio-demographic data, xerostomia, burning mouth, depression and anxiety symptoms, and sleep disturbances were applied. Measures of salivary flow rates were obtained using spit method. Correlation of hyposalivation and quantitative data was determined using a multivariate regression model. RESULTS: The age range was 31-83 years, hyposalivation was correlated positively with sleep disorder (β=0.079, 95% CI, to 0,124) and negatively with burning mouth (β=-0.043, 95% CI, -0.083 to -0.002). CONCLUSION: These results provide evidences regarding the association between reduced salivary flow and burning mouth, sleep disorders and chronic use of psychotropic medicines, and we highlighted the important role of antidepressants on modulation of burning mouth sensation...

JUSTIFICATIVA E OBJETIVOS: A saliva tem um papel importante na saúde bucal; está envolvida na lubrificação da mucosa oral, na proteção contra infecções, no transporte de nutrientes e enzimas digestivas, na remineralização dentária e também auxilia na mastigação, deglutição e fala. Sabe-se que reduções na quantidade de saliva aumentam o risco de doenças bucais. Este estudo investigou os fatores associados a alterações no fluxo salivar e seu relacionamento com idade, síndrome de ardência bucal, distúrbios psiquiátricos e do sono, doenças sistêmicas e uso crônico de medicamentos. MÉTODOS: Foi incluído um total de 30 pacientes com queixa de xerostomia sem doenças sistêmicas desequilibradas. Foram aplicados questionários sobre dados sociodemográficos, xerostomia, ardência bucal, sintomas de depressão e ansiedade e distúrbios do sono. As medidas de fluxo salivar foram obtidas pelo método spit. A correlação entre hipo-salivação e dados quantitativos foi determinada por um modelo univariado de regressão. RESULTADOS: A idade various de 31;83 anos, hipo-salivação foi correlacionada positivamente com distúrbios do sono (β=0,079, 95% CI, 0,033 a 0,124) e negativamente com ardência bucal (β=-0,043, 95% CI, -0,083 a -0,002). CONCLUSÃO: Esses resultados trazem evidências sobre a associação entre fluxo salivar reduzido e ardência bucal, distúrbios do sono e uso crônico de psicotrópicos, e destacamos o importante papel dos antidepressivos na modulação da sensação de ardência bucal...

Interrelação entre síndrome metabólica, estresse crônico e ritmos circadianos de marcadores adipogênicos: uma revisão / Interrelation between metabolic syndrome, chronic stress and circadian rhythms of adipogenic markers: a review

Alterações de ritmos circadianos são relacionadas ao desenvolvimento de transtornos metabólicos como obesidade e síndrome metabólica. Além disto, a disponibilidade e o consumo de alimentos altamente palatáveis ricos em gordura e a exposição a situações estressantes podem contribuir na incidência e na severidade destas doenças crônicas, provocando modificações no balanço energético, alterações no metabolismo de lipídeos e adipogênese. Nesta revisão, abordaremos os aspectos cronobiológicos que podem ser influenciados pela exposição a estresse crônico e a obesidade, além dos mecanismos que contribuem para o crescimento de doenças metabólicas (AU)

Alterations in circadian rhythms are associated with the development of metabolic disorders, such as obesity and metabolic syndrome. Moreover, the availability and consumption of highly palatable foods rich in fat and the exposure to stressful situations may contribute to the incidence and severity of these chronic diseases, leading to changes in energy balance, alterations in lipid metabolism and adipogenesis. This review aimed to discuss the chronobiological aspects that can be influenced by the response to chronic stress and obesity, as well as the mechanisms that contribute to the development of metabolic diseases (AU)

Avaliação de fatores associados ao diagnóstico de queimação bucal: um estudo preliminar / Evaluation of factors associated to diagnosis of burning mouth: a preliminary study

Objetivo: avaliar fatores associados ao diagnóstico de ardência bucal como xerostomia, hipossalivação, sintomas depressivos, ansiedade, transtornos de sono, doenças sistêmicas e uso contínuo de medicamentos. Métodos: foram avaliados 22 pacientes atendidos em nível ambulatorial através de escalas validadas e questionário sociodemográfico, seguido de medidas de fluxo salivar espontâneo e estimulado através do método de expectoração salivar. Na análise estatística descritiva foi utilizado SPSS 16.0. Resultados: a amostra foi composta por 4 homens e 18 mulheres com idade média de 61,6+2,83 anos. As médias de fluxo salivar espontâneo e estimulado foram 0,27+0,06 ml/min e 0,84+0,08 ml/min, respectivamente. A hipossalivação esteve presente em 54,5% dos casos, sendo que a xerostomia foi referida por 31,3% dos pacientes. Sintomas depressivos leves foram observados em 22,7% da amostra. Na avaliação de ansiedade-traço 31,8% apresentaram sintomas de ansiedade moderada, 63,6%, sintomas de ansiedade elevada e 4,5%, ansiedade muito elevada. Quanto à avaliação de ansiedade-estado 27,3% apresentaram sintomas de ansiedade moderada e 72,7% sintomas de ansiedade elevada. Setenta e sete por cento apresentaram alterações de sono. Os exames sorológicos não apresentaram alterações significativas. Conclusão: estes resultados sugerem associação entre os parâmetros comportamentais avaliados e os sintomas bucais, sendo necessário o aumento da amostra para que possamos confirmar estatisticamente essa tendência.

Aim: to evaluate factors associated with the diagnosis of burning mouth, such as dry mouth, hyposalivation, depressive symptoms, anxiety, sleep disorders, systemic diseases, and continuous use of medications. Methods: twenty-two patients recruited from outpatient clinics were assessed using validated scales and a sociodemographic questionnaire. Patients’ spontaneous and stimulated salivary flow rates were also measured using saliva expectoration. SPSS 16.0 was used in the descriptive statistical analysis. Results: the sample consisted of 4 men and 18 women whose mean age was 61.6±2.83 years. The mean of spontaneous and stimulated salivary flow rates were 0.27+0.06 mL/min and 0.84+0.08 mL/min, respectively. Hyposalivation was present in 54.5% of cases, and dry mouth was reported by 31.3% of patients. Mild depressive symptoms were observed in 22.7% of the sample. When assessing anxiety-trait, we found that 31.8% had moderate symptoms of anxiety, 63.6% had symptoms of high anxiety, and 4.5% had very high anxiety. The assessment of anxiety-status showed that 27.3% and 72.7% had moderate and elevated anxiety symptoms, respectively. Seventy-seven percent had sleep disorders. Serological tests showed no significant changes. Conclusion: Our findings suggest an association between the behavioral parameters evaluated and the oral symptoms, indicating the need for a larger sample to confirm this trend using statistical analysis.